PM2.5 Levels in Major Cities

Air quality in major cities around the world has assumed serious importance due to the high concentration of dangerous pollutants more so the PM2.5 particles that measure about 2.5 micrometers in size. PM2.5 levels in major cities usually exceed the safety limit recommended. PM2.5 is dangerously small enough to enter deeply into the lungs, hence creating a host of breathing ailments and other diseases affecting proper lung functioning.

It is not surprising to see the world stage becoming aware, the challenge of PM2.5 affects millions of people around the world. In this respect, we will present information on PM2.5 concentrations in major cities, along with causes, effects, and solutions.

PM2.5 Data in Major Cities Around the World

We present recent data as of this article is written on November 13, 2025, showing the most polluted locations in the world based on PM2.5 concentrations. In India, the highest levels are recorded in Defence Colony, Shahdara, and Delhi. In Pakistan, Multan and Faisalabad report the most critical readings. Meanwhile, in Kuwait, Kuwait City remains the most affected. All these areas consistently exceed the World Health Organization (WHO) air quality standards, making them among the most polluted cities globally.

New Delhi

Kuwait

Lahore

Factors Affecting PM2.5 Levels

In New Delhi and Lahore, during the winter season, air quality can exceed one hundred micrograms per cubic meter as temperature inversions, shallow boundary layers, weak winds, and high humidity trap pollutants near the ground. Combined with increased industrial and transportation emissions, this results in PM2.5 levels that are hazardous to human health. However in Kuwait, while winter has not fully set in, high PM2.5 levels can still occur due to dust, industrial activity, and traffic emissions, posing health risks to residents.

In comparison, and as evidenced by the PM2.5 levels in Europe and North America where PM2.5 are lower, more due to stricter emission standards like that of the US and Europe and to some extent efficiency in the industry are responsible for lower levels of PM2.5 than cities highlighted above.

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  AQI in the North American Cities on 13th November 2025. Source: iqair.com

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  AQI in the European Cities on 13th November 2025. Source: iqair.com

This comparison provides vast disparity in the management of air quality management across countries and further highlights that coordinated actions can address air quality in major cities worldwide.

Factors Causing High Pollution

High PM2.5 levels in major cities are due to a variety of interconnected factors, both from human activities as well as from natural conditions. You can directly attribute many of the impacts to the continuing rise in numbers of motorized vehicles. This rise creates exhaust emissions that release dangerous fine particles into the surrounding atmosphere.

The dams, the vehicles which are frequently caught in gridlock or idle with an engine running and increase the saturation of those polluting fine particles into the urban air. Additionally, heavy industry, alongside the burning of fossil fuels, releases considerable emissions that develop into PM2.5 in urban areas, including dangerous gases such as carbon monoxide and nitrogen dioxide, which promote PM2.5 formation.

Equally important, the open burning of waste and the usage of solid fuels such as wood or charcoal in households is another contributing factor to the increase of fine particles into the atmosphere. This is still observed in some areas, especially those without access to cleaner-burning types of energy.

Natural conditions also play into the situation. For example, cities located in a geographic location surrounded by mountains or valleys may restrict air circulation. Moreover, dry weather and low wind conditions may promote saturation of pollutant particles and make it difficult for them to disperse.

Social & Health Impacts

In large urban centers, high concentrations of PM2.5 in the air have numerous adverse effects on the community. Exposing humans to fine particulate materials can result in a range of respiratory issues. Airways can become irritated, and the risk of developing bronchitis or exacerbating previously diagnosed asthma conditions increases when exposed to particulate matter (also known as PM) levels.

PM (PM2.5 specifically) also contributes to cardiovascular problems such as coronary artery disease, heart failure, myocardial infarcts, and strokes, as these particles can enter blood circulation, causing inflammation of blood vessels.

The most vulnerable groups from these effects are children, the elderly, and people with chronic diseases, since their immune systems and respiratory systems are most susceptible to pollutants.

From a social perspective, air pollution also produces a net decrease in productivity at work because a number of people suffer from chronic health problems, and this directly translates into increased medical costs.

In addition, the overall quality of life for urban residents declines, as air pollution creates an unknown and unsafe environment. This also leads to social injustices, as lower income populations are typically located in areas of poor air quality.

AQI Comparison Between Countries

The Air Quality Index (AQI) is an internationally recognized way to measure levels of air pollution including PM2.5. The AQI score or level represents the level of cleanliness or pollution of the air at specific days and times. The scale goes from 0-500, and as the AQI level goes higher the pollution level also goes up, representing more risk to the public’s health.

While developed countries such as Japan, Germany, and Canada have lower AQIs and generally, better air quality, many developing countries in Asia and Africa have extremely high AQIs representing hazardous pollution levels. This is due to each country’s unique environmental policies, industrialization, and knowledge and practice of pollution control technologies.

Urban Solutions to Reduce PM2.5

One of the most effective approaches is to regulate and limit emissions from motor vehicles, which are significant contributors to urban air pollution. Governments can promote the use of low-emission public transport and stimulate the transition to electric vehicles, which produce markedly fewer emissions than their fossil fuel counterparts.

In addition, regular and strict monitoring of industrial processes and open burning of waste would also support such consequences. There also needs to be strategies for education and regulation that suit the areas where open burning takes place.

Also, development of green spaces, such as urban parks and plantings of trees, into urban regions are important. Plants can filter fine particles and toxins and vegetation has the effect of cooling air, resulting in lower ambient air temperatures.

Smart city technology is also being increasingly used to measure and manage air quality. Using air quality sensors integrated with smart ventilation systems can support more efficient pollution management in urban areas.

Final Note

Finally, raising public awareness and active engagement to the participation of proenvironmental behaviours are also important. For example, reducing their use of private vehicles, refusing to burn waste, and voting for green initiatives. Amid high PM2.5 levels in major cities, Legom offers smart solutions to create clean and comfortable indoor air.

Our Air Purifier products combine advanced filtration technology that effectively filters harmful fine particles. Meanwhile, our smart HVAC systems optimize air circulation and temperature regulation efficiently. With innovations trusted in more than 90 countries, Legomsmart helps you maintain your family’s health and improve the quality of life in polluted urban environments.